Exploiting Bananas for Novel Materials and Electro-Optical Devices

Michael-Rock Goldsmith

Duke University, Department of Chemistry

Chemistry 373 Seminar

11:50 a.m., 10/09/02 Room 103

Abstract:

Banana molecules, or bent-core molecules, are a unique class of ferroelectric liquid crystals (FLCs). The differences between the bent-core mesogen from conventional calamitic and discotic mesogens in terms of physical properties, symmetry, and phase formation are discussed and rationalized in terms of their unique structure. The enhanced polarization properties of the molecule, and their phenomenally fast relaxation times in an electric field give rise to superior electro-optical devices (and/or switches). Various novel experimental and theoretical approaches to understanding the B1-B7 LC phase formation are discussed, revealing the sudden interest in these mysterious bent-core molecules; Bananas exhibit homochiral domain formation in their twisted nematic phase despite being achiral.

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